.page-about {
  padding-bottom: clamp(56px, 9vw, 110px);
}

.page-about .about-head {
  padding-top: clamp(20px, 4vw, 42px);
}

.page-about .breadcrumb {
  margin-bottom: clamp(18px, 3vw, 30px);
}

.page-about .about-head__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(26px, 4vw, 46px);
}

.page-about .about-head__text h1 {
  margin: 10px 0 18px;
  max-width: 22ch;
}

.page-about .about-head__text .lead {
  max-width: 62ch;
}

.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: clamp(14px, 2vw, 22px);
  margin: clamp(26px, 4vw, 40px) 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-facts li {
  border-top: 1px solid var(--line-strong);
  padding-top: 12px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.page-about .about-facts .num-xl {
  font-family: var(--font-mono);
  color: var(--cyan);
  font-size: clamp(30px, 5vw, 46px);
  line-height: 1;
}

.page-about .about-facts__label {
  font-size: 13px;
  letter-spacing: .04em;
  color: var(--muted);
}

.page-about .about-index {
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  background: var(--panel);
  padding: 18px 16px 20px;
}

.page-about .about-index__title {
  margin: 0 0 12px;
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--muted);
}

.page-about .about-index__list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .about-index__list a {
  display: inline-block;
  padding: 7px 14px;
  border-radius: var(--r-pill);
  border: 1px solid var(--line);
  color: var(--white);
  font-size: 14px;
  text-decoration: none;
  transition: border-color .2s var(--ease), color .2s var(--ease), background-color .2s var(--ease);
}

.page-about .about-index__list a:hover,
.page-about .about-index__list a:focus-visible {
  border-color: var(--cyan);
  color: var(--cyan);
  background: rgba(53, 226, 208, .08);
}

.page-about .about-flow {
  margin-top: clamp(34px, 6vw, 76px);
}

.page-about .ab-board {
  border-radius: var(--r-xl);
  padding: clamp(22px, 4vw, 46px);
  position: relative;
}

.page-about .ab-board + .ab-board {
  margin-top: clamp(24px, 4.5vw, 58px);
}

.page-about .ab-board--paper {
  background: var(--paper);
  color: var(--ink-soft);
  box-shadow: var(--shadow-panel);
}

.page-about .ab-board--dark {
  background: var(--panel-2);
  color: var(--white);
  border: 1px solid var(--line);
}

.page-about .ab-board__head {
  margin-bottom: clamp(20px, 3vw, 32px);
}

.page-about .ab-board__no {
  margin: 0 0 10px;
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--muted);
}

.page-about .ab-board--paper .ab-board__no {
  color: rgba(16, 26, 38, .55);
}

.page-about .ab-board__head h2 {
  margin: 0;
  max-width: 26ch;
}

.page-about .ab-board__lede {
  margin: 14px 0 0;
  max-width: 66ch;
  color: rgba(247, 251, 255, .74);
  font-size: 16px;
  line-height: 1.75;
}

.page-about .ab-board--paper p {
  line-height: 1.8;
}

.page-about .ab-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 3.5vw, 44px);
  align-items: start;
}

.page-about .ab-split__text p {
  margin: 0 0 16px;
  max-width: 60ch;
}

.page-about .ab-split__text p:last-child {
  margin-bottom: 0;
}

.page-about .ab-split__media {
  border-radius: var(--r-lg);
  overflow: hidden;
  background: var(--paper-dim);
  margin: 0;
}

.page-about .ab-split__media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .ab-split__media figcaption {
  padding: 10px 14px;
  font-size: 13px;
  color: rgba(16, 26, 38, .7);
  background: var(--paper-dim);
}

.page-about .ab-board--dark .ab-split__media figcaption {
  background: rgba(247, 251, 255, .06);
  color: var(--muted);
}

/* 技能树 */
.page-about .about-tree {
  margin: 0 0 clamp(18px, 3vw, 28px);
  display: none;
}

.page-about .about-tree svg {
  width: 100%;
  height: auto;
  display: block;
}

.page-about .tree-links path {
  fill: none;
  stroke: var(--cyan);
  stroke-width: 1.5;
  stroke-dasharray: 5 6;
  opacity: .55;
}

.page-about .tree-node rect {
  fill: rgba(247, 251, 255, .04);
  stroke: var(--line-strong);
  stroke-width: 1;
}

.page-about .tree-node text {
  fill: var(--white);
  font-family: var(--font-body);
  font-size: 16px;
  font-weight: 600;
  text-anchor: middle;
}

.page-about .tree-node .tree-node__sub {
  fill: var(--muted);
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 400;
  letter-spacing: .04em;
}

.page-about .tree-node--core rect {
  fill: rgba(255, 122, 60, .14);
  stroke: var(--orange);
}

.page-about .tree-node--core text {
  fill: var(--orange);
  font-family: var(--font-display);
  font-size: 19px;
  letter-spacing: .06em;
}

.page-about .tree-node--blue rect { stroke: var(--league-blue); }
.page-about .tree-node--moss rect { stroke: var(--league-moss); }
.page-about .tree-node--wine rect { stroke: var(--league-wine); }
.page-about .tree-node--cyan rect { stroke: var(--cyan); }

.page-about .ab-treefallback {
  margin: 0 0 clamp(20px, 3vw, 30px);
  padding: 0;
  list-style: none;
  display: grid;
  gap: 10px;
}

.page-about .ab-treefallback li {
  border-left: 3px solid var(--cyan);
  padding: 8px 0 8px 14px;
  font-size: 15px;
  line-height: 1.7;
  color: rgba(247, 251, 255, .82);
}

.page-about .ab-treefallback strong {
  color: var(--white);
}

.page-about .ab-lines {
  display: grid;
  gap: 10px;
}

.page-about .ab-line {
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  background: rgba(7, 13, 24, .38);
  padding: 0 16px;
  transition: border-color .2s var(--ease), background-color .2s var(--ease);
}

.page-about .ab-line[open] {
  border-color: var(--line-strong);
  background: rgba(7, 13, 24, .6);
}

.page-about .ab-line summary {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 0;
  cursor: pointer;
  list-style: none;
  font-weight: 600;
  font-size: 16px;
  color: var(--white);
}

.page-about .ab-line summary::-webkit-details-marker {
  display: none;
}

.page-about .ab-line summary::after {
  content: "＋";
  margin-left: auto;
  font-family: var(--font-mono);
  color: var(--cyan);
  font-size: 15px;
}

.page-about .ab-line[open] summary::after {
  content: "－";
}

.page-about .ab-line__tag {
  font-size: 11px;
  letter-spacing: .1em;
  padding: 3px 9px;
  border-radius: var(--r-pill);
  border: 1px solid currentColor;
  color: var(--cyan);
}

.page-about .ab-line__tag.tag--blue { color: var(--league-blue); }
.page-about .ab-line__tag.tag--moss { color: var(--league-moss); }
.page-about .ab-line__tag.tag--wine { color: var(--league-wine); }
.page-about .ab-line__tag.tag--cyan { color: var(--cyan); }

.page-about .ab-line p {
  margin: 0 0 16px;
  padding-top: 4px;
  font-size: 15px;
  line-height: 1.8;
  color: rgba(247, 251, 255, .78);
  max-width: 68ch;
}

/* 联赛分区 */
.page-about .ab-league-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 3.5vw, 40px);
}

.page-about .ab-league-layout__text p {
  margin: 0 0 16px;
  max-width: 56ch;
}

.page-about .ab-league-stats {
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 10px;
}

.page-about .ab-league-stats li {
  display: flex;
  align-items: baseline;
  gap: 12px;
  border-top: 1px solid rgba(16, 26, 38, .18);
  padding-top: 10px;
  font-size: 15px;
}

.page-about .ab-league-stats .mono {
  font-size: 24px;
  color: var(--ink-soft);
  min-width: 4ch;
}

.page-about .ab-league-grid {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px;
}

.page-about .ab-league {
  display: flex;
  align-items: baseline;
  gap: 8px;
  padding: 12px 12px;
  border-radius: var(--r-sm);
  background: var(--panel);
  color: var(--paper-dim);
  font-size: 13px;
  border-left: 4px solid var(--league-blue);
}

.page-about .ab-league .mono {
  font-size: 13px;
  color: var(--muted);
}

.page-about .ab-league--blue { border-left-color: var(--league-blue); }
.page-about .ab-league--moss { border-left-color: var(--league-moss); }
.page-about .ab-league--wine { border-left-color: var(--league-wine); }

/* 团队 */
.page-about .ab-split--reverse .ab-split__text p {
  color: rgba(247, 251, 255, .8);
}

/* 时间线 */
.page-about .ab-board--timeline {
  overflow: hidden;
}

.page-about .ab-filter {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 12px;
}

.page-about .ab-filter .chip {
  cursor: pointer;
  border-radius: var(--r-pill);
  border: 1px solid rgba(16, 26, 38, .22);
  background: transparent;
  color: var(--ink-soft);
  font-family: var(--font-body);
  font-size: 14px;
  padding: 7px 16px;
  transition: background-color .2s var(--ease), color .2s var(--ease), border-color .2s var(--ease);
}

.page-about .ab-filter .chip[aria-pressed="true"] {
  background: var(--ink-soft);
  border-color: var(--ink-soft);
  color: var(--paper);
}

.page-about .ab-filter .chip:hover,
.page-about .ab-filter .chip:focus-visible {
  border-color: var(--cyan);
}

.page-about .ab-filter__status {
  margin: 0 0 22px;
  font-size: 12px;
  letter-spacing: .08em;
  color: rgba(16, 26, 38, .55);
}

.page-about .ab-timeline {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 0;
}

.page-about .ab-timeline__item {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 4px;
  padding: 18px 0 18px 20px;
  border-top: 1px solid rgba(16, 26, 38, .16);
  position: relative;
}

.page-about .ab-timeline__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 24px;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--orange);
}

.page-about .ab-timeline__item[data-hidden] {
  display: none;
}

.page-about .ab-timeline__year {
  font-size: 26px;
  line-height: 1;
  color: var(--ink-soft);
  letter-spacing: .02em;
}

.page-about .ab-timeline__body h3 {
  margin: 0 0 6px;
  font-size: 17px;
  font-weight: 600;
}

.page-about .ab-timeline__body p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: rgba(16, 26, 38, .78);
  max-width: 58ch;
}

.page-about .ab-timeline__media {
  margin: clamp(18px, 3vw, 30px) 0 0;
  border-radius: var(--r-lg);
  overflow: hidden;
  background: var(--paper-dim);
}

.page-about .ab-timeline__media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .ab-timeline__media figcaption {
  padding: 10px 14px;
  font-size: 13px;
  color: rgba(16, 26, 38, .7);
  background: var(--paper-dim);
}

/* 合作生态 */
.page-about .ab-partners {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
}

.page-about .ab-partners__cell {
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  padding: 18px;
  background: rgba(7, 13, 24, .35);
}

.page-about .ab-partners__cell .num-xl {
  font-family: var(--font-mono);
  font-size: clamp(30px, 5vw, 44px);
  line-height: 1;
  color: var(--cyan);
}

.page-about .ab-partners__unit {
  font-size: .5em;
  margin-left: 2px;
  color: var(--orange);
}

.page-about .ab-partners__cell p {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

.page-about .ab-awards {
  margin: clamp(20px, 3vw, 30px) 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 10px;
}

.page-about .ab-awards li {
  display: flex;
  align-items: baseline;
  gap: 14px;
  border-top: 1px dashed var(--line-strong);
  padding-top: 12px;
}

.page-about .ab-awards__year {
  color: var(--orange);
  font-size: 14px;
  letter-spacing: .06em;
}

.page-about .ab-awards p {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: rgba(247, 251, 255, .82);
}

/* 收尾 */
.page-about .ab-cta {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
  align-items: center;
}

.page-about .ab-cta__text h2 {
  margin: 0 0 10px;
}

.page-about .ab-cta__text p {
  margin: 0;
  max-width: 52ch;
  font-size: 15px;
  color: rgba(16, 26, 38, .78);
}

.page-about .ab-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .ab-cta__actions .btn {
  text-decoration: none;
}

/* 平板以上 */
@media (min-width: 700px) {
  .page-about .ab-split {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, .95fr);
  }

  .page-about .ab-split--reverse {
    grid-template-columns: minmax(0, .95fr) minmax(0, 1.05fr);
  }

  .page-about .ab-split--reverse .ab-split__media {
    order: -1;
  }

  .page-about .ab-league-layout {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, .95fr);
    align-items: start;
  }

  .page-about .ab-league-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .ab-partners {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .ab-timeline__item {
    grid-template-columns: 96px minmax(0, 1fr);
    gap: 20px;
    padding-left: 26px;
  }

  .page-about .ab-timeline__year {
    font-size: 30px;
  }

  .page-about .ab-cta {
    grid-template-columns: minmax(0, 1.2fr) auto;
  }
}

/* 桌面 */
@media (min-width: 900px) {
  .page-about .about-head__grid {
    grid-template-columns: minmax(0, 1fr) 240px;
    align-items: start;
  }

  .page-about .about-index {
    position: sticky;
    top: 92px;
  }

  .page-about .about-index__list {
    flex-direction: column;
    flex-wrap: nowrap;
  }

  .page-about .about-index__list a {
    display: block;
    border-radius: var(--r-sm);
    border-color: transparent;
    border-left: 2px solid var(--line);
    padding: 8px 12px;
  }

  .page-about .about-index__list a:hover,
  .page-about .about-index__list a:focus-visible {
    border-left-color: var(--cyan);
    background: rgba(53, 226, 208, .07);
  }

  .page-about .about-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-tree {
    display: block;
  }

  .page-about .ab-treefallback {
    display: none;
  }

  .page-about .ab-board:nth-of-type(odd) {
    margin-right: clamp(0px, 3.5vw, 54px);
  }

  .page-about .ab-board:nth-of-type(even) {
    margin-left: clamp(0px, 3.5vw, 54px);
  }

  .page-about .ab-partners {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .ab-cta {
    grid-template-columns: minmax(0, 1.1fr) auto;
  }
}
<<<END>>>